Infrared reflectors are used in various applications and preferably have as high reflectance as possible. In a heater that uses a heating wire or a halogen lamp, an infrared ray, radiated from the heating wire or the halogen lamps, is reflected by the reflective plate to irradiate the object. If the reflectance of this reflective plate can be increased, the object can be irradiated with the infrared ray with higher efficiency. Also, if the infrared ray contained in a sunray falling on houses can be reflected efficiently by an inexpensive reflective plate, the increase in room temperature inside the houses in summer can be reduced, thus cutting down the power dissipated by air conditioning systems and eventually saving the power rates.
An infrared reflector for heaters and so on may be a reflective plate made of aluminum, for example. As an infrared reflector to be attached to glass, a multilayer infrared reflective film is known.
Patent Document No. 1 discloses a reflective structure that is shaped as a mesh of a metal compound. FIG. 14 illustrates the configuration of the reflective structure disclosed in Patent Document No. 1. The reflective structure shown in FIG. 14 includes a glass base 1 and an infrared reflector 2 arranged on the glass base 1. The infrared reflector 2 is made of a metal compound and has a number of substantially square holes 3. Each side of the holes 3 is defined to be approximately half as long as the shortest wavelength of the infrared rays to be reflected (which will be referred to herein as an “infrared cut wavelength”). That is why infrared rays, of which the wavelengths are equal to or longer than the infrared cut wavelength, are reflected by the reflective structure without passing through the holes 3 of the reflective structure. Those holes 3 function as a waveguide for radiations that have shorter wavelengths than the infrared cut wavelength (e.g., visible radiation). Consequently, visible radiation is not reflected from the reflective structure but transmitted through the holes 3.    Patent Document No. 1: Japanese Patent Application Laid-Open Publication No. 7-43526 (see Paragraphs #0016 and #0023 and FIG. 1, in particular)    Patent Document No. 2: U.S. Pat. No. 5,079,473